staging: comedi: adv_pci_dio: remove 'valid' member from private data

This member is set at the end of the driver attach and is only used to
verify that pci_dio_reset() can be called in the (*detach). The only
requirement for pci_dio_reset() to work is that the dev->iobase is valid.

Remove the 'valid' member from the private data and use 'dev->iobase' to
see if the reset can be done.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/adv_pci_dio.c

@@ -393,7 +393,6 @@ static const struct dio_boardtype boardtypes[] = {
 };
 
 struct pci_dio_private {
-	char valid;		/*  card is usable */
 	char GlobalIrqEnabled;	/*  1= any IRQ source is enabled */
 	/*  PCI-1760 specific data */
 	unsigned char IDICntEnable;	/* counter's counting enable status */
@@ -1155,8 +1154,6 @@ static int pci_dio_auto_attach(struct comedi_device *dev,
 	if (this_board->cardtype == TYPE_PCI1760)
 		pci1760_attach(dev);
 
-	devpriv->valid = 1;
-
 	pci_dio_reset(dev);
 
 	return 0;
@@ -1164,12 +1161,8 @@ static int pci_dio_auto_attach(struct comedi_device *dev,
 
 static void pci_dio_detach(struct comedi_device *dev)
 {
-	struct pci_dio_private *devpriv = dev->private;
-
-	if (devpriv) {
-		if (devpriv->valid)
-			pci_dio_reset(dev);
-	}
+	if (dev->iobase)
+		pci_dio_reset(dev);
 	comedi_pci_detach(dev);
 }